int main()
{
//shape
typedef Flower2D<Z2i::Space> Flower;
Flower2D<Z2i::Space> flower(Z2i::Point(0,0), 20, 5, 5, 0);
//! [shapeGridCurveEstimator-dig]
//implicit digitization of a shape of type Flower
//into a digital space of type Space
double h = 1;
GaussDigitizer<Z2i::Space,Flower> dig;
dig.attach( flower );
dig.init( flower.getLowerBound()+Z2i::Vector(-1,-1),
flower.getUpperBound()+Z2i::Vector(1,1), h );
//! [shapeGridCurveEstimator-dig]
//! [shapeGridCurveEstimator-prepareTracking]
//Khalimsky space
Z2i::KSpace ks;
ks.init( dig.getLowerBound(), dig.getUpperBound(), true );
//adjacency (4-connectivity)
SurfelAdjacency<2> sAdj( true );
//! [shapeGridCurveEstimator-prepareTracking]
//! [shapeGridCurveEstimator-tracking]
//searching for one boundary element
Z2i::SCell bel = Surfaces<Z2i::KSpace>::findABel( ks, dig, 1000 );
//tracking
vector<Z2i::Point> boundaryPoints;
Surfaces<Z2i::KSpace>
::track2DBoundaryPoints( boundaryPoints, ks, sAdj, dig, bel );
//! [shapeGridCurveEstimator-tracking]
//! [shapeGridCurveEstimator-instantiation]
Z2i::Curve c;
c.initFromVector( boundaryPoints );
//! [shapeGridCurveEstimator-instantiation]
DGtal::Board2D aBoard;
aBoard << c;
aBoard.saveEPS("DisplayGridCurve1.eps");
//! [shapeGridCurveEstimator-getRange]
//range of points
typedef Z2i::Curve::PointsRange Range;
Range r = c.getPointsRange();
//! [shapeGridCurveEstimator-getRange]
//! [shapeGridCurveEstimator-lengthEstimation]
//length estimation
DSSLengthEstimator< Range::ConstIterator > DSSlength;
DSSlength.init( h, r.begin(), r.end(), c.isClosed() );
double length1 = DSSlength.eval();
trace.info() << "Length (h=" << h << "): " << length1 << endl;
//! [shapeGridCurveEstimator-lengthEstimation]
//@TODO correct init method of trueLengthEstimator (remove &flower)
//! [shapeGridCurveEstimator-trueLengthEstimation]
typedef ParametricShapeArcLengthFunctor< Flower > Length;
TrueGlobalEstimatorOnPoints<
Range::ConstIterator,
Flower,
Length > trueLengthEstimator;
trueLengthEstimator.init( h, r.begin(), r.end(), &flower, c.isClosed());
double trueLength = trueLengthEstimator.eval();
trace.info() << "ground truth: " << trueLength << endl;
//! [shapeGridCurveEstimator-trueLengthEstimation]
//! [shapeGridCurveEstimator-higher]
//implicit digitization at higher resolution
h = 0.1;
dig.init( flower.getLowerBound()+Z2i::Vector(-1,-1),
flower.getUpperBound()+Z2i::Vector(1,1), h );
//a greater domain is needed in the Khalimsky space
ks.init( dig.getLowerBound(), dig.getUpperBound(), true );
//searching for one boundary element
bel = Surfaces<Z2i::KSpace>::findABel( ks, dig, 10000 );
//tracking
Surfaces<Z2i::KSpace>
::track2DBoundaryPoints( boundaryPoints, ks, sAdj, dig, bel );
//reset grid curve and its points range
c.initFromVector( boundaryPoints );
Range r2 = c.getPointsRange();
//estimate length
DSSlength.init( h, r2.begin(), r2.end(), c.isClosed() );
double length2 = DSSlength.eval();
trace.info() << "Length (h=" << h << "): " << length2 << endl;
//! [shapeGridCurveEstimator-higher]
aBoard.clear();
aBoard << c;
aBoard.saveEPS("DisplayGridCurve01.eps");
return 0;
}
